It has been called VIP Spa, King Spa, Montage Massage & Day Spa and now, Du Soleil — although it has no sign marking it as a massage parlor, just some curtain-covered windows in a storefront strip mall and a red and blue light declaring it "OPEN."

On 14 visits to this non­descript establishment over the past two years, vice officers have arrested 23 women for agreeing to sex dates. Yet the Richmond Avenue enterprise is open for business - one of at least 550 massage parlors that have operated illegally in the city of Houston, according to court documents, data and public reports.

A Houston Chronicle analysis found 292 establishments have been cited by police for compliance violations, including operating without a state license, hiring unlicensed workers, operating during prohibited hours or engaging in vice crimes.

Another 260 advertise their services but don't appear in state licensing records.

"There are so many that open and close so fast, change names and change ownerships," said Sgt. Mark Kilty of the Houston Police Department Vice Division. "We definitely can't keep track of all of them."

Many are suspected of serving as fronts for prostitution, authorities across the county say.

Among those with the most violations is the business at 9413 Richmond.

Last year, the Houston city attorney issued an injunction against the property owner, who, in turn, evicted the King Spa (previously known as VIP Spa). It opened again with a new name, first as Montage Massage & Day Spa and then as Du Soleil, with a new owner in the same spot in the same strip mall from which it was evicted.

"This is the kind of quandary we get stuck in," said senior assistant city attorney Nirja Aiyer. "You close them up, they think no one is looking, then they go right back at it."

Neighbors complain

The city of Houston provided the Chronicle with a list of 30 massage parlors, spas and modeling studios that have been closed down over the past two years, mostly for posing a "public nuisance." And yet a simple Web search found five advertising "grand openings" in online classified ads this month.

The newly named Du Soleil advertised a grand opening on Oct. 21 featuring nearly bare photos of what the site called "Latin Beauties."

Deputy Gerald Hull, of the Harris County Precinct 5 Constable's Office, told the Chronicle they have received multiple complaints from neighbors.

"People in the opposite side of the spa said they see repeated customers coming in and out the place after midnight," Hull said.

Regulating massage parlors is a dubious task. They often change names and ownership, if they register with authorities at all.

The job of licensing and inspecting them falls to Texas Department of State Health Services, but the state relies heavily on local police to enforce the regulations. There is just one full-time state investigator assigned to routine inspections of licensed businesses. Five investigators, shared with other state programs, review and investigate complaints against licensees.

But department spokeswoman Christine Mann said the massage licensing program could be eliminated as part of a series of proposed budget cuts, though any decision to do so would be made by the Texas Legislature.

"One of those options is to eliminate our massage therapy licensing program, worth $1.5 million over the 2012-2013 biennium," Mann wrote in an e-mail.

More than 150 establishments have been cited by the police for prostitution since 2008; 70 of them have been raided three or more times, records show. Many, if not most, are still operating.

Parade of owners

On North Beltway 8, for example, the Golden Beach Spa - known now as the Essence Spa - has been targeted seven times and seen the arrests of 15 women ranging in age from 20 to 41.

It has had at least three owners, according to Harris County records. The first, Xiao Fei Li, was convicted of operating Green Haven Spa, a different business, without a license in March.

The latest registered owner is Johnna Boyd, who also is the registered owner of Bluelite Adult Video next door. She says she no longer owns the spa but doesn't know to whom she sold it.

The business owner for the Richmond Avenue VIP spa was 43-year-old Long Xiu Zhao until 2008. In March 2009, he was charged by Harris County constables with operating yet another spa without a license.

The state health department also took his Litz Massage Therapy Spa, another business in Katy, because of sexual misconduct and other violations in August 2009.

The Richmond business has never been registered with the state.

A warrant has been issued for Zhao, who could face up to one year in Harris County Jail and a $4,000 fine. Public records show he has lived in Houston, New Orleans and New York.

"We get a triangle here. They come from New York, California. They rotate every few months," said Hull, of the Precinct 5 Constable's Office.

Most of the places that have been cited by law enforcement officers are concentrated in the Montrose-Midtown area and in southwest Houston.

But Capt. Skip Oliver of the Precinct 4 Constable's Office said after the city passed stiffer ordinances in 2007, officers began seeing an influx of the establishments onto county roads like FM 1960 and Texas 6.

"There are so many unoccupied strip mall centers that are certainly less expensive than the city, so they are looking to do anything to rent the space," said Oliver.

Drag on local economy

The influx has further depressed the economy of the community, local business people say.

"The more the business degraded, the fewer people move here. It's hard to do business here," said Larry Lipton, who owns an insurance agency on FM 1960.

The city has an ordinance prohibiting massage parlors from operating between 10 p.m. and 8 a.m., but the county does not.

Most of the time, it's the women who work in massage parlors who get arrested. One 29-year-old woman has been fined four times for "practicing massage therapy without registration." She pays a $350 fine every time the court calls her in.

City changing tactics

But police say the women don't seem concerned about fines.

"Losing money is part of the business," said Cpl. Ernest Gonzalez, with the Precinct 4 Constable's Office. "The fine is nothing compared to what they make."

Another 32-year-old woman has been fined five times but has paid nothing so far.

"They do not want to run a legitimate business. They want to make money and do it quickly," said Linda Geffin, division chief of special prosecutions with the Harris County Attorney's office.

Among the 526 license violation cases filed in Houston Municipal court, more than half were dismissed. Most of the time that was because the police officer who was called to testify did not show for court. Cases that involve a prostitution arrest get higher priority, authorities say.

"With prostitution arrests, it's easier for us to turn around and shut these places down," said David Feldman, the city attorney.

He said the city is now looking at a shorter path - closing down the illegal ones as public nuisances rather than waiting for criminal convictions.